edoc

Quantitative Insights into Charge-Separated States from One- and Two-Pulse Laser Experiments Relevant for Artificial Photosynthesis

Neumann, Svenja and Kerzig, Christoph and Wenger, Oliver S.. (2019) Quantitative Insights into Charge-Separated States from One- and Two-Pulse Laser Experiments Relevant for Artificial Photosynthesis. Chemical Science, 10 (21). pp. 5624-5633.

[img] PDF - Published Version
Available under License CC BY-NC (Attribution-NonCommercial).

1243Kb

Official URL: https://edoc.unibas.ch/73100/

Downloads: Statistics Overview

Abstract

Charge-separated states (CSSs) are key intermediates in photosynthesis and solar energy conversion. However, the factors governing the formation efficiencies of CSSs are still poorly understood, and light-induced electron–hole recombinations as deactivation pathways competing with desired charge accumulations are largely unexplored. This greatly limits the possibility to perform efficient multi-electron transfer, which is essential for artificial photosynthesis. We present a systematic investigation of two donor–sensitizer–acceptor triads (with different donor–acceptor distances) capable of storing as much as 2.0 eV in their CSSs upon the absorption of a visible photon. Using quantitative one- and two-pulse laser flash photolysis, we provide deep insights into both the CSS formation quantum yield, which can reach up to 80%, and the fate of the CSS upon further (secondary) excitation with green photons. The triad with shorter intramolecular distances shows a remarkable excitation wavelength dependence of the CSS formation quantum yield, and the CSS of this triad undergoes more efficient light-induced charge recombination than the longer equivalent by about one order of magnitude, whilst thermal charge recombination shows the exact opposite behavior. The unexpected results of our detailed photophysical study can be rationalized by detrimental singlet charge transfer states or structural considerations, and could significantly contribute to the future design of CSS precursors for accumulative multi-electron transfer and artificial photosynthesis.
Faculties and Departments:05 Faculty of Science > Departement Chemie > Chemie > Anorganische Chemie (Wenger)
UniBasel Contributors:Wenger, Oliver and Neumann, Svenja and Kerzig, Christoph
Item Type:Article, refereed
Article Subtype:Research Article
Publisher:Royal Society of Chemistry
ISSN:2041-6520
e-ISSN:2041-6539
Note:Publication type according to Uni Basel Research Database: Journal article
Language:English
Identification Number:
Last Modified:13 Dec 2019 14:09
Deposited On:13 Dec 2019 14:05

Repository Staff Only: item control page